The 2015 Kansas City Chiefs season was the franchise's 46th season in the National Football League, the 56th overall and the third under the head coach/general manager tandem of Andy Reid and John Dorsey. The Chiefs went through a poor start in their first 6 games as they were 1–5, and lost their star running back, Jamaal Charles due to a torn ACL in his right knee during an 18–17 Week 5 loss at home against the Chicago Bears. In week 16, after their 9th consecutive victory and the Baltimore Ravens defeating the Pittsburgh Steelers, the Chiefs clinched a playoff berth, their 2nd in 3 years.[1] They are the first team since the 1970 Cincinnati Bengals to start the season 1–5 and qualify for the playoffs.[2] They also set the franchise record for the most consecutive victories, winning 10 in a row. In their wildcard matchup, the Chiefs played the Houston Texans. The Chiefs defeated the Texans 30–0 to earn their first playoff win in 22 years. The following week, they were defeated by the New England Patriots in the Divisional round by a score of 27–20.

Cairo Santos would kick 7 field goals in this game, setting a new franchise record for most field goals in one game by a Kansas City kicker. The 7 kicks also tied an NFL record. However, the 7 field goals by Santos were not enough to beat the Bengals, as the Chiefs fell to 1-3.

The Chiefs would build a 17-3 lead at one point, but Chicago would pull off a miraculous comeback to win 18-17. The Chiefs tried a 66-yard field goal, but Santos kick went wide right and missed everything near the goalposts. During this game, the Bears fans at times outnumbered the Chiefs fans, as Chicago fans are best known for good travel.

With the loss, Kansas City fell to 1-4. They would also lose Jamaal Charles for the season, as he tore his ACL in this game.

Ben Roethlisberger would not play in this game for the Steelers, so backup quarterback Landry Jones led the way for the Steelers. In his first career start, the Chiefs defense would force 3 turnovers, 2 of them interceptions, and the Chiefs would hold on to win 23-13.

Broncos quarterback Peyton Manning would set the all-time record for most passing yards in NFL history in this game, but the Chiefs defense would have themselves a day, picking off Bronco quarterbacks 5 times, 4 by Manning, 1 by Brock Osweiler, and the Chiefs routed the Broncos, 29-13.

With the win, the Chiefs went to 4-5, and snapped their 7-game losing streak against the Broncos.

The Browns, led by Johnny Manziel, attempted a comeback to put a stop to Kansas City's playoff hopes, but Cleveland did not have any timeouts remaining, and they ultimately ran out of time when Manziel couldn't advance the ball down the field fast enough.

With their 10th straight win, the Chiefs ended their season at 11-5. They were the first team to end a season with 10 or more consecutive wins since the 2012 Broncos won 11 in a row to end their season.

The Texans, who won the AFC South division with a 9–7 record, were completely crushed by the Chiefs. The Chiefs made postseason history as the first ever team to score a kick return touchdown in the opening play of the playoffs, when Knile Davis returned the opening kick 106 yards for a touchdown. After that, the game started to slow down, 3 and out Texans, 3 & out Chiefs, followed by a string of turnovers, Eric Berry's interception of Brian Hoyer, Brian Cushing's interception of Alex Smith two plays later, and a Hoyer fumble recovered by Dontari Poe on the ensuing drive. The Chiefs made a field goal on the drive, and although the team was able to get to the 2 yard line, a negative run by J. J. Watt and another interception by Hoyer ended the Texans' closest chance at scoring in the entire game. Although the Texans' defense forced a 3-and-out, Hoyer threw his third interception to Marcus Peters on the second play of their drive.

The Chiefs, who had won 11 straight, travelled to Gillete Stadium to face the Patriots, who had advanced to the AFC Championship for the last 5 years. The Patriots scored first blood with a Rob Gronkowski touchdown catch, followed by a Cairo Santos field goal for Kansas City. The pattern was duplicated in the 2nd quarter, with Tom Brady rushing for a score before Santos kicked another field goal. In the 3rd quarter, after Gronkowski scored his second TD, Alex Smith threw his first to Albert Wilson. The Patriots responded with 2 fourth quarter field goals to make the score 27-13 with 10:20 left. Although the Chiefs go on a touchdown drive late in the game, the drive took up over 5 minutes, and the Chiefs had to force a 3 and out (with 3 timeouts) to have a chance. On 2nd down, when Brady threw the ball instead of running it to waste time, the ball was batted and miraculously caught by Julian Edelman for a 1st down, ending the game.